German Patent Application No. DE 195 27 218 A1 describes a quantity-compensation control. In that case, disparities in the fuel quantity injected into the individual cylinders are inferred from irregularities of the crankshaft rotation, thus, from the extent of the cylinder-specific rotational accelerations within one working cycle. This is based on the following consideration: The heat released during a combustion in the combustion chamber is converted into mechanical work upon expansion of the gas in the cylinder, and accelerates the crankshaft. Ideally, the torque shares of all cylinders of an engine are identical. In reality, however, this is not the case. Differences in the torque shares give rise to differences in the acceleration of the crankshaft, which can be recorded by a speed sensor. In many operating situations, different torque shares are caused by different injection quantities, and can be offset by a cylinder-specific correction of the injection quantity when working with the quantity-compensation control described at the outset.
Moreover, German Patent Application No. DE 10 2004 046 083 A1 describes a method in which a sensor is disposed at a guide cylinder, by which a feature characterizing the combustion can be obtained for this guide cylinder. The other cylinders are adapted to this guide cylinder with the aid of a compensation functionality. This method is advantageous primarily for those combustion processes which have a great ignition lag, e.g., what are referred to as partial homogeneous combustion processes.